December 23, 2008

Cuarto Creciente

If you were interested in the Moon a few decades ago, or have some of Dinsmore Alter's old lunar books you may remember the entire Moon images that they contained, nearly one for each day of the lunation. The photographs were taken with the Lick 36" refractor and were stunning. Vicente's mosaic with an amateur's 10" telescope reminds me of the pleasure of looking at such sharp lunar phase images. And I am also transported back to my first observing with a good telescope - a 4.3" Alvin Clark refractor on the University of Arizona campus. Dramatic features, then and now, are the black bites out of the terminator where a circular crater floor has not yet been rotated into the sunrise. Further north along the terminator are long triangular shadows from peaks in the Apennines and Caucasus mountains. And then on to check the poles and the rest of the limb (look, Humboltianum is just visible) to see what libration reveals. Observing with a good scope is always an encounter I enter with high expectation of welcoming old crater friends, being surprised by something new, and enjoying the richness of another world.